Job offers
Post-doctoral position: Quantum-inspired approaches for the simulation of turbulent flows
Tensor networks are widely used in quantum mechanics to effectively and dramatically reduce the number of degrees of freedom required to represent complex quantum states. More recently, they have also emerged as a promising approach to represent and simulate various classical systems including turbulent flows.
The aim of this post-doctoral project is to explore the simulation of turbulent flows using tensor networks. The goal will be to determine whether such approach can enable the investigation of high Reynolds number flows which are out of reach for traditional methods, or whether a low-order model based on this representation can capture the main statistical features of turbulent flows. The methods will then be applied to investigate fundamental aspects of turbulent flows and the emergence of extreme events in turbulence.
Expected start date: September or October 2026
Project duration: 18 to 24 months
See PDF file for more details.
PhD position: Waves and turbulence in rotating superfluid helium-4
Near absolute zero, liquid helium-4 enters a superfluid phase known as He II where it displays unique hydrodynamical properties. At finite temperatures between about 1 and 2 K, He II can be seen as a mixture of a viscous normal fluid and a superfluid without viscosity, whose rotational degrees of freedom are concentrated on so-called quantum vortices with atomic-scale thickness and quantised intensity. Remarkably, when He II is set in rotation, quantum vortices tend to align with the rotation axis and form a highly regular vortex lattice. When perturbed by external mechanisms, rotating He II can host a variety of wavelike motions, such as inertial waves propagating through the fluid as in classical rotating flows, but also waves which are specific to the singular nature of vortices in He II. As the perturbation is intensified, a disordered state known as rotating quantum turbulence (QT) can be triggered, which is still today very poorly understood.
In this PhD project, we will study the mechanisms leading to the destabilisation of the rotating quantum vortex lattice by external perturbations and the fully turbulent states beyond that. We will characterise the spatial structure of quantum vortices in rotating QT and aim at unveiling possible similarities with classical rotating turbulence, where inertial waves play a major role and where scale-by-scale energy transfer mechanisms are strongly altered by rotation. To study these fundamental mechanisms, we will perform the first numerical simulations of rotating QT in spatially-homogeneous settings, which is enabled by a novel numerical method recently developed at LEGI. Our numerical results will be quantitatively compared to experimental measurements in a rotating platform at Institut Néel, where quantum vortices can be directly visualised. This project will substantially advance our understanding of rotating He II flows, in particular in transitional and fully turbulent regimes where experimental measurements become very challenging. It will also reinforce the analogy between classical and quantum turbulence, potentially leading to novel approaches for modelling turbulent flows in classical fluids.
Expected start date: 1 October 2026
Project duration: 36 months
See PDF file for more details.
